A displacement machine of this type, the principle of which is known from German Patent Specification No. 2,603,462 C2, is suitable for supercharging an internal combustion engine, because its remarkable feature is a substantially pulsation-free delivery of the working medium comprising for example, air or an air-fuel mixture. During the operation of spiral superchargers of this type, crescent-shaped working chambers are enclosed along the delivery chamber between the displacer and the two peripheral walls of the delivery chamber. These working chambers move from the inlet through the delivery chamber toward the outlet. At the same tme, their volume is reduced to an increasing extent as the pressure of the working medium is correspondingly raised.
A machine of the type mentioned at the outset is known from German Patent Specification No. 3,141,525 A1. In the disclosed compressor, two displacers attached on a rotor intermesh. The delivery chambers pertaining to them in the stationary housing in each case run from an inlet chamber, provided at the outer periphery of the housing, to an outlet chamber which is provided at the inner periphery of the housing and through which the compressed working medium is discharged. The centrally arranged drive shaft for the rotor, together with a part of the shaft mounting and the rotor bearings, are also accommodated inside the housing. The hot, compressed air flows around these parts and therefore they are inaccessible to cooling. In particular, there is no longer any space available for accommodating cooling chambers as are known, for example, from the above-mentioned German Patent Specification No. 2,603,462 C2 and which also need to be connected to a separate cooling circuit.
It is therefore the object of the present invention to create a displacement machine of the type mentioned at the outset in which heat dissipation can take place during compression.